Targeted online advertising may be an important source of revenue for enterprises engaged in electronic commerce. Processes associated with technologies such as Hypertext Markup Language (HTML) and Hypertext Transfer Protocol (HTTP) enable a web page to be configured to display advertisements. Those advertisements may be targeted based on a user's preferences. In addition to advertisements, other material and resources on a web page may also be targeted for a particular user. Accurate targeting typically requires an identification of a user and knowledge regarding that identified user. The knowledge may include demographics, past browsing history, past purchasing history, or other information that can help to understand a user. In certain situations, it may be difficult to identify a user and/or obtain knowledge regarding that user.